. Annual report. 1st-12th, 1867-1878. Geology. 678 GEOLOGICAL SURVEY OF THE TERRITORIES. vol. 11, jp. 190), "In the common Fowl each carotid * * * enters (ing) the canal formed by the ; In the completed twelfth vertebra of mature birds we find this hypapophysis very large, with expanded extremity, and the parapophy- sis, on either side, sending down long subsquamous processes. In the thirteenth segment of the " bird of the year " theparapophyses begin to take on a change. This change develops in the adult still a perfect hypa- pophysis, but in the younger indiv
. Annual report. 1st-12th, 1867-1878. Geology. 678 GEOLOGICAL SURVEY OF THE TERRITORIES. vol. 11, jp. 190), "In the common Fowl each carotid * * * enters (ing) the canal formed by the ; In the completed twelfth vertebra of mature birds we find this hypapophysis very large, with expanded extremity, and the parapophy- sis, on either side, sending down long subsquamous processes. In the thirteenth segment of the " bird of the year " theparapophyses begin to take on a change. This change develops in the adult still a perfect hypa- pophysis, but in the younger individual the parapophysial element begins to be notched anteriorly, a part favoring the pleurapophysis, a part the centrum, so that in the fourteenth vertebra of the adult the hypapophysis is still present anteriorly with a tubercle developing on either side of it, with the parietes of the vertebral canal very much slenderer. In examining this segment in the younger bird we ascertain that the original ossicle is now a descending pleurapophysis meeting the parapophysis, a delicate and independent process, which, in the fif- teenth and last cervical vertebra, constitutes a free rib, while the hypapo- physis consists of a mid-process and a smaller nodule on either side. This beautiful metamorphosis can be thoroughly studied and easily com- prehended in the cervical portion of the vertebral column in our Gaihar- tes aura. So that, as a partial .recapitulation of the first fifteen segments, we find that they make up the " cervical portion" of the column. Their cen- tra are universally subcompressed at their middles, they develop in the young bird parapophysial projections that eventually produce free ribs by the aid of the descending pleurapophyses, and their interarticula- tions, as far as their bodies are concerned, bear out the general ornithic law of being apparently proccelous on vertical section and opisthocce- lous on horizontal section. Backwards from the fifteenth th
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